EARTH & LIFE SCIENCE (MODULES 1-4) SUMMARY

EARTH AND LIFE SCIENCE

1. EARTH & LIFE SCIENCE
SUMMARY OF MODULE 1 - 4
MODULE 1 Origin and Structure of the Earth (Planet)
Origin of the Earth
The Earth formed about 4.6 billion years ago from a huge cloud of gas
and dust in space. This process is called the Nebular Hypothesis.
Here’s how it happened:
• The cloud of gas and dust started to spin and come together
because of gravity.
• Most of the material formed the Sun.
• The remaining dust clumped together to form the planets,
including Earth.
At first, Earth was a hot, melted ball, but over time it cooled down. The
surface hardened to form land, and gases formed the atmosphere.
Water appeared, and life eventually began.
Real-life example: The Moon rocks brought back by astronauts help
scientists study the early history of Earth and the solar system.

Shape and Size of the Earth
• Earth is not a perfect circle. It is slightly flattened at the top and
bottom (the poles). This shape is called an oblate spheroid.
• Earth’s diameter is about 12,742 kilometers.
Real-life example: Satellite images of Earth from space show its round
but slightly squished shape.

Structure of the Earth
The Earth is made up of four main layers, like layers of an onion:
1. Crust
o The outermost layer. It’s solid and thin.
o This is where we live. NAME:_______________________________________
DATE:_______________________________________

2. o It includes land (continents) and seafloor.
2. Mantle
o Found beneath the crust.
o Made of hot, soft rock that can slowly move.
o This movement causes earthquakes and volcanoes.
3. Outer Core
o Made of liquid metal (mostly iron and nickel).
o It creates Earth’s magnetic field.
4. Inner Core
o Solid and very hot.
o Also made of iron and nickel.
o Even though it's hot, it's solid due to high pressure.
Real-life example: Earthquakes help scientists study the Earth's layers.
The way earthquake waves travel tells us what's inside the Earth.

MODULE 2 Origin and Structure of the Earth (The Subsystems)
What are Earth's Subsystems?
Earth is made up of four main subsystems that are always interacting
with each other. These are:
1. Geosphere
2. Hydrosphere
3. Atmosphere
4. Biosphere
These subsystems work together to support life and maintain balance
on Earth.

1. Geosphere – The Solid Earth
• Includes the rocks, mountains, soil, and landforms.

3. • It is the solid part of the Earth, from the surface to the inner core.
• Provides natural resources like minerals, oil, and metals.
Real-life examples:
• Volcanoes, mountains, caves
• Earthquakes and landslides

2. Hydrosphere – All Water on Earth
• Includes oceans, rivers, lakes, glaciers, and even underground
water.
• Also includes water vapor in the air.
• Covers about 71% of Earth’s surface.
Real-life examples:
• The Pacific Ocean, rain, drinking water
• Water used for farming and electricity (hydropower)

3. Atmosphere – The Layer of Air Around Earth
• A mix of gases (mostly nitrogen and oxygen) that surround Earth.
• Protects us from harmful rays of the Sun.
• Helps regulate temperature and provides oxygen for breathing.
Real-life examples:
• Weather and climate
• Airplanes flying in the sky
• Breathing fresh air

4. Biosphere – All Living Things
• Includes plants, animals, humans, and microorganisms.
• Lives in or interacts with the other three subsystems.

4. • The biosphere depends on water, land, and air to survive.
Real-life examples:
• Forests, farms, coral reefs
• Humans building homes, farming, and fishing

How Do These Subsystems Work Together?
The subsystems are connected and affect one another.
Example:
• During a volcanic eruption (geosphere), gas and ash go into the
atmosphere, lava destroys plants and animals (biosphere), and
nearby rivers may be blocked (hydrosphere).
This is called an Earth system interaction.

MODULE 3 MINERALS
What is a Mineral?
A mineral is a naturally formed, non-living solid that has:
• a definite shape
• a specific chemical makeup
• an ordered internal structure
5 Key Properties of Minerals:
1. Naturally Occurring – Found in nature, not made by people.
o Example: Gold found in rivers.
2. Inorganic – Not made by living things.
o Example: Salt (from the sea or mines).
3. Solid – Always solid at room temperature.
o Example: Ice is a mineral (but water is not).
4. Definite Chemical Composition – Made of specific elements.

5. o Example: Quartz is always made of silicon and oxygen
(SiO₂).
5. Crystalline Structure – Atoms are arranged in a repeating
pattern.
o Example: Diamond has a crystal pattern that makes it very
hard.
Common Mineral Examples in Real Life:
• Quartz – used in glass and watches.
• Halite – table salt (used in cooking).
• Talc – used in baby powder.
• Calcite – found in limestone, used in building materials.
• Graphite – found in pencils.
• Gold – used in jewelry.

MODULE 4 ROCKS
What is a Rock?
A rock is a solid combination of minerals or mineral-like materials.
Rocks are made of one or more minerals.
3 Types of Rocks:

1. Igneous Rocks – From Cooling Lava or Magma
• Formed when magma (inside Earth) or lava (outside Earth)
cools and becomes solid.
Examples:
• Granite – used in countertops (cooled slowly underground)
• Basalt – used in road construction (cooled quickly from lava)

2. Sedimentary Rocks – From Layers of Sediments

6. • Formed from sand, pebbles, or shells that are pressed and
cemented together over time.
Examples:
• Sandstone – used in buildings and paving
• Limestone – used in cement and chalk
• Shale – used in making bricks and tiles

3. Metamorphic Rocks – Changed by Heat and Pressure
• Formed when existing rocks are changed due to heat and
pressure deep in the Earth.
Examples:
• Marble – used in statues and buildings (from limestone)
• Slate – used in roofing (from shale)

Rock Cycle (Simple Explanation)
• Rocks can change from one type to another over time.
• Example: Magma cools → Igneous Rock → breaks down →
Sediments → Sedimentary Rock → heat & pressure →
Metamorphic Rock
Summary Chart:
Term Simple Definition Examples
Mineral Natural, solid, non-living substance Quartz, Gold, Salt, Talc
Rock Made of one or more minerals Granite, Sandstone, Marble
Igneous Formed from cooled magma/lava Basalt, Granite
Sedimentary Formed from compressed
sediments
Limestone, Shale,
Sandstone
Metamorphic Rocks changed by heat and
pressure
Marble (from limestone),
Slate

7. Worksheet: Earth's Subsystems
Name: ___________________________
Date: ___________________________
Grade/Section: ___________________

Part A: Matching Type
Match the subsystem to its description. Write the letter of the
correct answer.
A. Geosphere
B. Hydrosphere
C. Atmosphere
D. Biosphere
1. _____ All living things on Earth, like plants and animals
2. _____ Solid part of Earth such as rocks and soil
3. _____ Layer of gases that surround the Earth
4. _____ All water on Earth, including oceans and rivers

Part B: Multiple Choice
Choose the letter of the best answer.
5. Which of the following is an example of the hydrosphere?
A. Trees
B. Mountains
C. Rivers
D. Clouds
6. What makes up the biosphere?
A. Air and wind
B. Living organisms
C. Rocks and soil
D. Ocean water

8. 7. Why is the atmosphere important?
A. It provides metal resources
B. It stores water
C. It gives oxygen to breathe
D. It produces plants
8. Which subsystem includes volcanoes and mountains?
A. Biosphere
B. Hydrosphere
C. Geosphere
D. Atmosphere
9. Which of the following is NOT part of the geosphere?
A. Soil
B. Ocean
C. Rocks
D. Mountains
10. Which two subsystems interact when plants take in
carbon dioxide from the air?
A. Geosphere and Biosphere
B. Hydrosphere and Atmosphere
C. Atmosphere and Biosphere
D. Geosphere and Hydrosphere
11. Which event shows interaction between the
geosphere and atmosphere?
A. A bird flying
B. A fish swimming
C. A volcanic eruption releasing gases
D. A tree growing in soil
12. What is one way humans affect the hydrosphere?
A. Cutting down trees
B. Burning fossil fuels
C. Throwing trash in rivers
D. Mining rocks